I am having probs with my ageing PC, and would like to postpone the purchase of a new one for another few months, if possible.

Boot-up caused much wailing from the Beast and I found I could get to bootup by removing one of my RAM chips. (ddr1, 1MB)......

Inserting a known good one led to dire warnings from the BIOS. Firstly it sed set the PC speed right in BIOS (AMD 3200+) but it was set to 200, which my local Linux-friendly dealer sed wos OK (Phoenix Award Bios v6.00PG, for acer <R01-A4>.

It also complains of CMOS checksum error.

No matter how I try I cannot get the Beast to store BIOS changes to cache. Setting the clock right, reset config data. new battery for BIOS and setting su and user pwds at the start and end of a session still means that I can not get it to boot first from CD. There seems no way out for me since I have defaults from the start. However, I can get a stable Mate GUI.

I loaded LXF166 DVD and wished to start Disaster Recovery Kit. I can select it and select autorun but I get the msg
Autorun not found.

With regards to the RAM. Check the stick is properly seated in the slot. Check there is nothing (dust or debris) in the slot causing a bad connection.

From your post I guess you have more than one stick of RAM installed. What results do you get if you put the one you first removed back in and remove the other/s? If you have two or more sticks try removing all but one, then booting the machine. Rinse and repeat for each stick in turn. If one of the sticks is bad you will soon know. It's unlikely but possible to have a duff RAM slot. so Try each stick in the same slot. eg, stick 1 slot 1, stick 2 slot 1. Then stick 1 slot 2 and stick 2 slot 2 etc.

The BIOS problems sound like a faulty battery. I know you said you have already tried a new one. I would get another new one and try again. Or at lest test the battery with a Multimeter.

When you say that you cannot boot from CD. Do you mean that you have set the CD drive as the first boot device in the BIOS but the boot order is not persistent? Some BIOS have a different key to be pressed during the POST to select a boot device that is different to the default behaviour. Sort of a change for this time only feature. For example each time my PC boots I can press F2 to enter the BIOS to change the boot order permanently or F12 to select boot device for this session.

Ah, I see. Memtest is a kernel, you have to boot from it, you cannot run it within an OS (because it would not be able to properly test any memory in use by the OS). The autorun script is not in your path, so you have to give the path to run it

I had to go to have some medical tests done so that is why I am late in replying.

I have tried for hours to find a manual for the motherboard for an Acer Aspire 360 AMD-64, 3200+ but with no luck so far. I shall to continue, but I will take your advice first and use F12 to boot from CD and explore LXF166 for memtest and see where it takes us.